Utqiagvik_seaice_2021 Raw sequence reads. Utqiagvik_seaice_2021

Alaska landfast sea ice forms along the Arctic coast to an isobath of approximately 20 m. Here, it serves a vital role for subsistence and industrial activities, shoreline stabilization, and marine mammal habitation. Sea ice also serves as a habitat for diverse microbial communities that contribute to regional biogeochemical cycling and food web dynamics. During the vernal ice-algal bloom, microalgal biomass concentration can reach several orders of magnitude greater than in the underlying seawater, and is largely confined to the lowermost centimeters of sea ice. We explored the prokaryotic and eukaryotic microbial communities in the bottom 10-cm of sea ice from the onset of the ice algal bloom into the early melt season and investigate the physical drivers responsible for community shifts and bloom termination. We further leverage our data to identify potential interactions between ice algae and their parasitoids and succession. Sampling took place near Utqiagvik, AK between April to mid-June of 2021 on level, landfast sea ice. Sampling procedures followed the protocol established during the Multidisciplinary Drifting Observatory for the Study of Arctic Climate (MOSAiC). These time-series data will help to identify the relationship of physical and biogeochemical controls of microbial community development and primary production.